Lubricant



which may be ities, probably mula:

which the group S in the above graphic for- Patented Nov. 7, 1944 PATENT OFFICE 1 LUBRICANT Pharis Miller, Elizabeth,

Staten Island, N. Y.,

Development Compan ware 7 No Drawing.

This invention relates to a novel type of metal compound and methods of preparing same, and

relates more particularly to the use of these novel compounds as addition agents in hydrocarbon compositions, especially lubricating oils, for improving same.

It has been found that hydrocarbon compositions, especially hydrocarbon lubricating oils, are greatly improved by adding thereto a small amount of metal compound such as an aluminum "salt of tertiary amyl phenol thio-ether, which might also be called a sulfide of an aluminum tertiary amyl phenolate. It is believed to have the .torm'ula, shown in its simplest form as:

uomn-cem-onsiemlv written out more in detail as follows:

n the various groups attached to the aromatic nucleus are so positioned that the amyl group is in an ortho position to the oxygen and the sulfur linkage is in a meta position to the oxygen, this compound, although it might have other possibilhas the following graphic lor- It should be understood that the position or the various substituents around the aromatic nu-' cleus maybe varied without departing from the scope of the invention.

A similar disulfide compound may be used in even potassium salts thereof, as by treatmentwith so 55 Application December 27, Serial No. 311,118

7 21 Claims.

N. J., and Eugene Lleber, assignors to Standard Oil. y, a corporation of Deladium or potassium hydroxide and then converting the resultant derivative of the group I metal into the corresponding derivative of the group III metal, such as aluminum, by suitable means such taining at least one grouping having the general iormula: l

3 -M-Y-Ar(X)e 20 wherein M represents the metal constituent connectedthrough Y to at least one aromatic nu- I cleus, Y is an element in the right hand side of group 6 of the periodic table (Mendeleefl), Ar is an aromatic nucleus, which contains like or unlike substituents, X, n in number, replacing nuclear hydrogen, 1 being at least one.

Thesubstituents, X, may be organic, inorganic, or both, for example, alkyl radicals and groups containing one or more of the non-metallic ele- 30 ments belonging togroups V, VI, and VII of the 7 Al A o t o o f e o 0-H" Cr clan can. can cine s-O ssperiodic system (Mendeleefl): nitrogen, phosphorus, oxygen, sulfur, and halogens, as in amino,

nitro, phosphite, phosphate,'hydroxy, alkoxy, sultide, thioether, mercapto, chloro groups, and the like.

In the, phenolatesalts constituting blending agents featured by this invention, valences of the metal other than those connected to the substituted phenolic radicals, such as -O-Ar(X)n, are connected through oxygen to other organic groups or to inorganic constituents, such as hydrogen,. phosphorus, etc. For convenience,- non-phenolic radicals or groups, as well as phenolic' groups, attached to the metal are indicated broadly by 0-R' in the following types of compositional formulae, which broadly represent metal derivatives of substituted phenolic comerably a molecular weight below about 40, con- I 2 ascaaoo pounds containing the characteristic composi- It is preferred that if the substituted metal tional grouping described: phenolates contain an inorganic substituent attacheduigktldietgrgmaific niigleus, or an organic group e ug an organic elemen 9 should preferably be sulfur, as in the case of the 0-3 alkyl phenolate thioethers or polysulfldes. How- 1 (KM ever, although not as good, corresponding metal on derivatives of the following substituted phenolic compounds may be used, in which an inorganic O-ArGU- substituent other than sulfur is used:

M-o-aix):

HO(R)CsHsO-CcHa(R)-OH [H0(R)CaHs-]3P HO(R)CsI-IsOCH:-CoH4-OH HO-(R)CeHaCHz-OCOHs (R')-OH w HO(R)Ccm-P(OH)CsHa(R)0I-I o (x I-I0(R) CeHaCH2NH.-CoHs(R) OH o'Aflxi HO-(R)CsHs--CH(Cl)-CH2COH3(R)OH ,M O,B Especially preferred are compounds containingat least one grouping having the general formula: (l 0 o-mx). 0M

). M-o-a:(x).al- -o-M it a-L-zrwhere M is the metal, Ar is an aromatic nucleus, Specifically illustrating some of the structures R is an organic group, Z is a member of the sulm the substituted phenolates may have, fur family, and n is an integer of 1 to 5, Z is prefaromdtic nuclei are indicated in the conventional manner by-being represented by benzene nuclei of compositions 'CsHr, 'CeHr, etc., with x, as before, standing for nuclear substituents (e. 8., CnH:n+1, -NO2, -Cl, -S-,- 8:.-, NH:, NH(CnH2a+i), etc.)

mo-cenr-(xia-ctm (X)--OM Corresponding metal derivatives of the following types of substituted phenolic compounds can be used, in which R represents an all!!! Group,

preferably having at least 4 carbon atoms:

- HS-(R) cim-s-dimmi-on no-(n) cens-s-cinp-n 5 naphthalene,

erably sulfur, and n is preferably 1 or 2, although for some specific purposes it may be 3 or more. R represents an organic group which may be either aryl, alkyl, arallryl or cycloalkyl,

and which may contain substituent groups such as halogen, particularly chlorine, nitro, nitroso, amino, hydroxy, carboxy, alkoxy, aroxy, mercapto,and the like, but preferably is or contains an alkyl or alkylenyl group, and preferably contains at least 4 carbon atoms but may contain many more, such as 8, 10, 16, 18, etc.

The configurations of the compounds are not limited to certain positions in the illustrated structures, for the substituents may be in ortho, para, or meta relations to one another. Also, the

substituents, X, in any aromatic nucleus may be alike or different.

The aromatic nucleus may be polycyclic as in phenanthrene, di'phenyl, etc. Where oxygen occurs, it may be replaced by sulfur, selenium, or tellurium, as in thiophenols.

An important feature of this invention issues from the observation that metal phenolates are 5 benefited in solubility and effectiveness as hydrocarbon lubricaij lg oil blending agents when they contain a total of at least 8 and preferably of at least 10 carbon atoms per molecule in aliphatic grouping when sulfur is present in no the molecule, and preferably at least 16 carbon atoms if no sulfur is present, preferably in aikylradicals present as aromatic nuclear substituents. Another valuable feature is that inorganic substituents, particularly negative inorganic groups containing non-metallic elements of groups V, VI, and VII of the Mendeleefl Periodic System, beneficially influence the phenolates by increasing their potency for stabilizing the lubricating oils and by making the phenolates,

m in themselves.- more stable, as for instance,

against hydrolysis.

Specific examples of preferred substituted phenolates falling into the classes mentioned,

having a monoor tri-valent constituent, e. g.,

I! sodium. potassium. aluminum, etc., and having an alkyl radical as a substituent are formulated as follows:

e. g., salts of tert-amyl phenol salts of tert-octyl phenol II. Alkyl chlorphenolater) e. g., salts of 2 chloro, itert-amyl phenol salts of 2,6 dichloro, 4 tert-amyl phenol salts of 6 chloro, 2,4 diamyl phenol HI. Alkyl amino phenolates M'O'CGHHNHD (email) M-o-ctm-NH-cman e. g., salts of amyl, para-amino phenol salts of N-amyl, para-amino phenol Thioethers of alkyl phenolates e. g., thioether of salts of tert-amyl phenol V. Disulfides of alkyl phenolates q (M-o-csm-cnnmmsz e. g., salts of tert-amyl phenol disulflde VI. Alkyl nitrophenolates M'O'C6H3(NO2) (CnHsnfl) I e. g., saltsof alkyl nitrophenol sulfide As these substituted phenolates are generaly made by reacting the corresponding phenols with a metal oxide or hydroxide (either the one desired, or the sodium or potassium compounds to nit-AH) zsmMi a: is 1 or 2, and n is the valency of such metal. and more particularly still. the following general formula:

'ua-c m-onshan In these latter two formulas R. represents one or more alkyl groups having enough carbon atoms, preferably at least 10. to insure solubility of the total compounds in mineral oil. Instead of aluminum, gallium or other metals of group III of the periodic table may be used, although aluminum is preferred. 1 I

For the objects stated, the metal phenolates have been preferably prepared from phenolic Suitable synthetic 'alkyl phenols for prepar- If only part of the sowhere M is a metal having avalency of LM 3,,

ing the desired phenola'tes are principally of the secondary and tertiary types, because alkylation' of a simple phenol occurs more readily with branched aliphatic reactants. Commonly, 'the alkylation reaction involves a condensation of olefins with the simple phenols, the reaction being catalyzed by anhydrous metal halides, sul- .furic acid, phosphoric acid, or certain activated I clays. As olefinic reactants, refinery gases con-' mixtures from other sources may be used. The reaction temperature is usually controlled to avoid side reactions. In employing sulfuric acid, a I liquid phase reaction at relatively low temperatures is preferred; with phosphoric acid the reaction may be carried out in the vapor'phase.

As starting materials for conversion into the metal phenolates, the phenols may contain one or more substituents which provide a desired "number of saturated carbon atoms in groups having the form of straight chains, branched chains, or even rings. phenols are synthesized conveniently by alkylating a phenol with a branched chain olefin poly-' mer, such as diisobutylene, di-tert-amylene, or other suitable agents, such as alcohols, alkyl sulfates, alkyl phosphates, or alkyl halides, thereby forming a carbon-to-carbon bbnd between the aromatic nuclei and the alkyl groups.

Petroleum phenols which qualify for the present purpose are considered to contain polymethyene or cycloalkyl side chains, as evidenced by their hydrogen and carbon analysis. The petroleum phenols are obtained by extraction of various stocks, chiefly from cracking process heat! 'ing oil stocks, with caustic soda, and acidification of the alkaline extract with a weak mineral acid followed by a non-destructive distillation, if desired.

By using the described methods or any other.

well known method for preparing alkyl phenols,

45 the following alkylated phenols, i. e., may be" procured for preparing the phenolates: tert-amyl phenol, iso-hexyl phenol, tert-octyl phenol. ditert-butyl phenol, etc.

Inorganic substituents are introduced into alkyl phenols by well known methods. For exam- .ple, an alkyl phenol, e. g. tert-amyl phenol, is reacted with sulfur mono-chloride, SaClz, in about a l: /2 mole ratio and preferably in a solvent such as dichlorethane, to produce the alkyl phenol disulflde. Using substantially the same procedure but substituting sulfur. dichloride,

SClz, for the mono-chloride, the alkyl phenols are given a thioether linkage substltuent. Alkyl chlorphenols are obtained by chlorination, preferably controlled to replace nuclear hydrogen by a chloro group. This may be accomplished by chlorinating the phenol before alkylation. In such a manner, for example, 2-chlor-4-tertamyl phenol can be produced. Nitro substitu- 05 ents' are introduced readily into the aromatic nucleus by d rect nitration, and nltro substitu ents can be reduced to amino groups. It is to be understood, however, that the preparation of substituted phenolic compounds which have been described does not form part of this invention and that any of the well known methods for their production may be used.

The invention will be better understood from a consideration of the following experimental data: Y i

Ill)

taining propylene, butylenes, amylenes, etc., are economically useful, although; individual ole-. fins, e. g. isobutylene, iso-amylene, di-isobutylvene, .tri-isobutylene, etc., or olefin-containing Mono-alkyl or poly-alkyl Exsurra 1 39 parts by weight (1 6 mole) of tertiary amyl phenol thioether (made accordingto U. 8. Patent 2,139,321) were dissolved in alcohol, and

parts by weight of an alcoholic solution of potassium hydroxide were slowly added with stirring, and the resulting alcoholic solution was evaporated to dryness on a steam bath. The residue was the potassium salt or tertiary amyl phenol thioether, which might otherwise be called the thioether of tertiary amyl potassium phenolate. (A slight excess of the phenol thioether was used to insure the absence or free alkali.)

The product was soluble in mineral oil. An

0.2% blend of this product was made in a commercial parafllnlc type lubricating oil having the following inspection:

Gravity A. P. I 29.2 Flash point F 445 Viscosity Saybolt at 100 F 385 Viscosity Saybolt at 210 F 56 Pour point V F; 20 Color, Robinson 8 /2 Conradson carbon residue percent 0.107

The original oil and the blend were subjected to several tests to determine their comparative tendencies to form sludge under various conditions.

Test

Cone Sligh Ori al .Q 0.45 24 mai 0.28 15 These tests show that the blend was superior to the original oil in both tests.

. Cone test This is a test to'determine the suitability of a lubricating oil foruse in internal combustion engines, and consists essentially in passing a small stream of the oil to be tested down an open spiral groove cut in the inner surface of a metal cone. The cone is maintained at 250 F. and the weight of carbonaceous deposit left by the oil is determined. Lower values indicate the best oil. The detailed procedure recommended for carrying out this test is described in Patent 2,174,021. sugh test This is a test of the tendency of an oil to sludge under oxidizing conditions and is described in the proceedings of the A. S. T. M. vol. 24, page 964, part II (1924), except that the oxidation is carried out for a period ortwenty-four hours. The result is expressedas the weight of sludge produced, and accordingly the lowest values indicate the best oil from this particular point of ether'itself has no load carrying capacity.

lopartsbyweightortbe potassium salts of tertiary my! phenol thioether, prepared as deasaaseo scribed above in Example 1, were disolved in absolute alcohol and 10.8 parts by weight or aluminum nitrate, A.l(NOs)a-9H20, dissolved in absolute alcohol were slowly added to it. The mixture was evaporated to dryness and the residue was extracted with ether, filtered and evaporated to dryness. The final residue was an aluminum salt of tertiary amyl phenol thioether and it was soluble in oil. A 0.2% blend (in the same commercial lubricating oil described in Example 1) caused no darkening oi the color and gave a cone test of 0.20 as compared to 0.45 for the orignal oil.

' Exsurrs 3- 200 parts by weight (.51 mole) of tertiary amyl phenol thioether dissolved in absolute alcohol,

were treated with 57.4 parts by weight (1.0 mole) of filtered alcoholic potassium hydroxide and the mixed solution was evaporated to dryness on a steam bath. The product, although not as soluble in mineral lubricating oil as the potassium salts prepared in Example 1 by the use oi. a slight excess of the tertiary amyl phenol thioether, was converted to the corresponding aluminum salt by adding an alcoholic solution of partially dried aluminum nitrate to an alcoholic solution of the potassium salt, using an excess of the aluminum nitrate. The mixed solution was extracted with ether and evaporated to dryness.

Exmrrs 4 173 by weight of tertiary amyl phenol thioether, 17.3 parts by weight of finely powdered sodium hydroxide, and 40 parts by weight of anhydrous aluminum chloride, were placed in a S-necked flask. The latter was heated to 150 C. with stirring, and the bath was heated at 130-l50 C. over night with continuous stirring. The residue was dissolved in ether and the ether solution was evaporated to dryness. The product was soluble in mineral oil and contained a substantial proportion of aluminum salt or tertiary amyl phenol thioether, although it apparently was not quite as pure as the aluminum salt prepared in Example 2. An 0.2% blend of the product in the same commercial lubricating oil used-in Example 1 gave a cone test of 0.29 compared to 0.45 for the original oil.

Exams: 5

. ing chemical analysis, the theoretical value based upon the formula [(CsHu'CeHs'OhShAh being also given tor-the sake of comparison:

has Theoretical Percent suliur 8. 04 s. 55

are 9.0 4.62 4.x

Exams: 6

.Thesodium salt or tertiary amyl phenol thioetherwaspreparedinthesamemannerlsused for potassium saltas described in Example 1 and the resulting sodium salt was treated with an absolute alcohol solution of aluminum chloride.

The aluminum salt of tertiary amyl phenol thioether was produced and was found to be soluble in a Diesel oil having a viscosity of 5'5 seconds Saybolt at 210 F. The sodium salt used in the preparation of'this aluminum compound, had been prepared from ahighly purified distilled tertiary amyl phenol thioether.

This procedure was repeated using a plant grade or relatively crude tertiary amyl phenol thioether as the starting material but the resulting aluminum salt of tertiary-amyl phenol thioether was likewise found to be soluble in the same Diesel oil.

Enlist]: 7

Exanru: 8

39 parts by weight (.1 mole) of tertiary amyl phenol disulflde were dissolved in alcohol and 16 parts by weight of caustic soda, also dissolved in alcohol,-were added and the whole solution evaporated to dryness. The residue is the sodium salt of tertiary amyl phenol disulflde.

This sodium salt was dissolved inalcohol and mixed with an alcohol solution of aluminum nitrate. The precipitate which forms is the aluminum salt of tertiary amyl phenol disuliide and it is filtered out, washed twice with water, and

dried.

Corresponding aluminum, etc. salts or other alkyl phenol sulfides may be prepared; for instance, by substituting polysulfldes or polymers such as the dimers, trimers, and tetramers, of the alkyl phenol thioetheradisulfldes, and the like, in place of the alkyl phenol thioethers used in the above examples. Also, the corresponding metal salts of the corresponding selenides and tellurides may be prepared, although the sulfur compound are preferred.

-afllnic, naphthenic, 'asphaltic, or mixed crudes 4 metals. At the same time, the metal compounds. of this invention possess the distinctly unexpect- The various products obtained may be purified,

if desired, by fractional crystallization, extraction, precipitation with selective solvents, etc.

with suitable adsorptive agents such as clay.

While these compounds or mixtures thereof, alone or in admixture with corresponding alkyl phenol sulfides, may be added in any desired concentration within their solubility limits to 111- bricating oils,-they are preferably used in 0011s centrations of about 0.01 to 2.0%, about 0.1- to 1.0% being generally suflicient to impart oxidationand sludging-resistant properties to the majority of lubricating oils. Larger amounts up to 5% or more may be used to improve the lubrieating or oiliness characteristics ofthe-lubricatmg These metal compounds'may also be used as improving agents in other hydrocarbon oils or products, such aswaxQfl-fuel oils, Diesel fuels,

naphthas, gasoline, burning oil, and the like.-

These metal compounds may also be used as improving agents in products derived from pe: troleum oils or in different types of products such as fatty oils, soaps, aldehydes, resins, rubber, pa-

per, and various synthetic products which tend to deteriorate by oxidation either alone or in accompaniment with other chemical phenomena.

The metal compounds of this invention are especially useful for improving mineral lubricating oils, particularly those used for crankcase lubrication of internal combustion engines, and other oils which are usedat elevated temperatures such as above 150 or 200 C. These oils'm'ay be obtained from various. types of crudes such as parsuch 'as paraflinic, naphthenic, asphaltic, or

mixed crudes,'and they may. be'either plain distillates or fractions obtained by treating or refining in various methods known to the art such as acid treating, clay treating, solvent extraction,

dewaxing, etc., or they may be synthetic oil's resulting from varous types of chemical reactions such as cracking, polymerization, condensation,

and the like.

In preparing-finished lubricants according to .thisinvention, other known addition agents may.

also be used such as dyes, soaps, sludge dispersers, solvents, etc.

pour inhibitors, oxidation inhibitors, mutual Although the invention is of primary impor- '1 tance for preparing Diesel engine lubricants, it is also useful for other types of crankcase lubricants, steam cylinder oils, greases, upper cylinder lubricants, slushing oils, etc.

The invention has numerous advantages, some of which are apparent from the pre e ing discussion, butit should also be pointed out that the invention provides unexpectedly useful results in making aluminum available in oil-soluble form: this is surprising because aluminum soaps seem to be substantially less soluble in mineral oils than soaps'of other metals such as the heavy ed advantage that they have very substantial anti-oxidant properties. On the other hand, aluminum stearate of the prior 'art is not oil-soluble v and usually forms gels in the lubricating oil,

particularly when cooled down from high temperature and also upon long standing, and yet soluble metal compounds such as lead naphthenate usually greatly increase the oxidation rate of the oils to which they are added. The aluminum I agent. There is also evidence to indicate that Also, impurities mayb removed by treatment they act to some extent as anti-polymerizing agent's, especially in oils used at relatively high temperature such as Diesel engine lubricants.

These and other advantages of the invention will be-still better understood from-an examination of the following engine test data:

7 Exam ne 9 v 1.5% 'of aluminum salt of tertiary amyl phenol thioether was dissolved in a Diesel lubricating oil base stock having the following characteristics:

The oil was obtained from a Coastal crude.

' cent of reference" and is Demerit:

- having the following inspection:

Both the original oil and the blend were subiected to a test in the C. F. R. (Cooperative Fuel Research) engine for 14 hours at 375 F, jacket temperature, using 2% lbs. of oil in the charge. After each run, the engine is taken down, inspected, and rated by demerits (the lower the better) according to the condition of the piston parts, valves and cylinders. The demerit rating of the blank oil is represented as 100 and the reference rating of the blend is expressed as percalculated as follows:

P cent f f en blend demeritX 100 er re er 0 blank oil demerit The lower the percent of reference, the better the oil according to this engine test.

The results of these engine tests are tabulated as follows:

Name or type oi test Original oil tertiary amyl henol t loether 34. l3, l4, l5, 14

These results indicate that although the aluminum salt of tertiary amyl Phenyl thioether slightly accelerated the oxidation rate of this particular lube oil base stock, it caused a remarkable improvement in the general condition of the engine at the end of the test by reason of the lower demerits, lower amount of carbon formed, and

lower S. D. Sligh (sludge) figure.

The oxidation test, referred to above, comprises oxidizing the oil under certain specified conditions and determining the amount of oxygen (measured in cubic centimeters) absorbed in successive 15' minute intervals.

EXAMPLE 10 0.5% of an aluminum salt of tertiary amyl phenol thioether was dissolved in a Diesel lubricating 011 base stock, made from 9. Coastal crude,

when this blend and the original oil were subjected to a Sligh test todetermine sludging tendencies, the results were as follows:

Bligh test Oil (mgs. of

I sludge) Original oil 61 riginal oil+0.5% aluminum compound 21.0

The blend containin the aluminum salt was superior to the original oil.

1.0% of this same aluminum salt was dissolved in the same original oil and the blend was subjected to an oxidation rate test along with the original oil for comparison, the results being as follows:

011 Oxidation mic (ccs. 0,115 min.)

Original oil 43-45-3941 Original oil-{4% aluminum compound -14-1443 These tests show that the aluminum salt of the tertiary amyl phenol thioether both reduces I the oxidation rate and sludge formation in this lube oil base stock.

EXAMPLE 11 0.25% of aluminum tertiary amyl phenol thioether was dissolved in another commercial lubricating oil base stock (S. A. E. 20) and both the blend and original oil were subjected to oxidation, Sligh, and C. F. R. engine tests, with the following results, also including results on a similar blend of the corresponding sodium salt of tertiary amyl phenol thioether:

Oxidation C. ra e average eng 0 on of first our Sugh per cent 15 min.) reference Original oil; 40 l. 9 I00 Original o1l+0.25% sodium compd. ll 10. 4 39 Original oil-H).25% Al m 2. 9 24 These tests indicate that although the sodium compound effected improvement in the engine performance of the lubricating oil base stock, the aluminum compound is even better because the latter showed a percent of reference of only 24. On the other hand, the sodium compound effected the greatest reduction in the oxidation rate and therefore although it was not as good as the aluminum compound in improving engine performance of the lubricating oil base stock, it still has value as an addition agent to other types of hydrocarbon oil for reducing the oxidation rate thereof.

. Exam 12 A 1% solution of aluminum salt of tertiary amyl phenol thioether in a naphthenic lubricating oil base stock'having a viscosity of 55 secs. Saybolt at 210 F. was subjected to a carbon .black dispersion test which is considered of interest in evaluating sludge dispersers for internal combustion engine lubricants. In this test, 450grams or the oil to be tested is heated to 225 F. and agitated in a Mix Master" during the stepwise addition of 30 grams of carbon-black. After 30 minutes of further stirring, the suspension is transferred to a graduated 500 cc. cylinder, settled for 22 hours in an oil bath at 200 F.,' and allowed to stand for an additional 2 hours at room temperature. In the absence of a dispersing agent, the carbon black settles out and leaves a clear supernatant layer oi oil, thevolume of which is recorded; the smaller this value. the better the dispersing power of the oil. In the presence of an effective disperser, however,

the volume or oil settled clear will be zero, or,

in other words, the carbon black remains suspended throughout the entire volume of oil in. the cylinder and in this case the eflectiven'ess-of the disperser is evaluated by determining the concentration of carbon black remaining in the suspension at a given volume from the top of the cylinder. For this purpose, a 10 cc. aliquot of the suspension is pipetted at a point 25 cc. below the surface of the mixture, diluted 'toan appropriate volume with naphtha, and the concentration of carbon black is determined by turbidimetric comparison with a standard suspension, reporting the results in terms of milligrams of. carbon percc. in suspension.

For comparison with the 1% solution of aluminum t. a. p. s.- (tertiary amyl phenol sulfide) a sample of the blank oil was also tested, as well as a solution of 1% of t. a. p. s. therein.

The results of these dispersion tests are summarized as follows:

Cc. MgC/cc. settled suspended Lube oil base stock 200 Lube oil base stock+l% t. a. p. s 145 0 Lube oil base stock+l% Alt. a. p. s 0 21 1 llhe naphthcnic lube oil having a viscosity of 55 sec. Saybolt at 210 These tests indicate. that the aluminum salt of the tertiary amyl phenol sulphide maintain the carbon black suspended throughout the entire volume of the oil (no-oil had settled clear), and theamount of carbon black held in suspension near the top of the cylinder was 21 milligrams of carbon per cc., which is a remarkably and unexpectedly high value, .since both the .blank oil and the blend containing 1% of the tertiary amyl phenol sulphide itself had a large volume of oil settled clear at the top and no carbon remained suspended near the top of the were given solely for the purpose of illustration,

nor by any theory as to the mechanism of the operation of "the invention, but only by the following claims in which it is desired to claim all novelty inherent in the invention as far as the prior art permits. v

-We.claim':

1. A lubricant comprising a major proportion of mineral lubricating oil and a small amount oi. a compound, containing at least one grouping having the general formula where M is a light metal having an odd valency,

Ar is an aromatic nucleus, R is an organic group, Z is a member of the sulfur family. and a: is an integer of 1 to 5.

3. A lubricant comprising a" major amount of mineral lubricating oil and a small amount of a group 3 light metal salt of an alkyl phenol sulfide.

4. A lubricant comprising a major proportion of mineral lubricating oil and a small amount of a sulfide of an aluminum alkyl phenolate.

5. A lubricant comprising a major proportion of a mineral lubricating oil and a small amount of a compound having the general formula [(R-C6H3O) 28] 3A1:

where R is an alkyl group having at least four carbon atoms in which the sulfur atoms are each linked directly to the benzene nuclei and a in which the aluminum atoms are each linked directly to the oxygen atoms.

6, A lubricant comprising a major proportion of a mineral lubricating oil and a small amount of a compound having the formula wherein R is analkyl group having at least fourcarbon atoms and in which the sulfur atoms are each linked directly to two benzene nuclei and to 35, a flash pointof about 350-500 F., a

viscosity of about 500 to 800 seconds Saybolt at 100 F. and about 40 to'75 seconds Saybolt at 210 R, and about 0.1.to 5.0% of an aluminum salt of .an alkyl phenol thloether each alkyl radical containing at least four carbon atoms.

10. Alubricant comprising a mineral oil base stock and a small amount of an oil-soluble alu- 2. A lubricant comprising a major proportion of mineral lubricating oil and a small amount of a compound having the general formula.

where Aris I an aromatic nucleus, R is an alkyl group. a: is an integer of 1 to 5, M is a light metal having an odd valency, and n is an integer corresponding to the valence of M, in which the in which the groups R, 13'

- eating oil and a small minum salt of the reaction product of a sulfur halide with an alkylated aryl compound having a hydroxy group attached directly to the aryl nucleus.

11. An improved mineral oil composition comprising a mineral oil having admixed therewith a mmor proportion of an oil miscible sulfide of an alkyl substituted aryl aluminum oxide in which the oxygen of the aluminum oxide group is d rectly attached to the-aryl nucleus and in which at least two alkyl substituted aryl nuclei are interconnected by at least one atom of sulfur.

12. An improved mineral lubricating oil composition comprising a mineral lubricating oil having admixed therewith a minor proportion of an 011 miscible aluminum salt of an alkylated phenol sulfide having the formula momcaHa-si-cenmn) R connected to an aromatic nucleus (Col-I3), R and R represent alkyl'groups (CnH2n+i) and a: represents an integer, 1 or 2.

13. A lubricant comprising a mineral lubriamount oi" an oil-soluble sulfide of a metal alkyl rality of phenol groups are attached to a single metal atom, said metal being a light metal-having an odd valency. r

OH and S: are each phenolate in which a plu single aluminum atom.

16. An improved mineral oil composition comprising a mineral oil having admixed therewith a minor proportion of an oil miscible sulfide of an alkyl substituted aryl sodium oxide in which the oxygen of the sodium oxide group is direct ly attached to the aryl nucleus and-in which at least two alkyl substituted aryl nuclei are interconnected by at least one atom of sulfur.

17,. An improved mineral oil composition comprising a. mineral oil having admixed therewith a minor proportion of an oil miscible sulfide of an alkyl substituted aryl potassium oxide in which the oxygen of the potassium oxide group is directly attached to the aryl nucleus and in which at least two alkyl substituted aryl nuclei are interconnected by at least one atom of sulfur.

asomoo 18. A lubricant comprising a major amount of a mineral lubricating oil and a minor amount of a compound having the formula wherein Ar is an aryl nucleus, R is an alkyl group having at least 4 carbon atoms and a: is an integer .of from 1 to 5.

19. A lubricant comprising a mineral lubricating oil and a small amount of the potassium phenol sulfide, each aliphatic radical containing at least four aliphatic carbon atoms.

PHARIS MILLER. EUGENE LIEBER. 

